MATHLIB Function
Return the value of the natural logarithm.
LN(X_FV)
X_FV
A positive, non-zero floating point value.
Description
Use this function to return the value of the natural logarithm as a floating point value.
Errors
LN: argument <= 0; returning -1.0.
X was not a positive, non-zero value, so the function returned the value -1.0 and placed this message in the ESL errorlog.